Save the Children spoke to civilians who have recently fled the country who told of a "death journey" on which some children were separated from their parents, with at least one 12-year-old boy being left behind to die on his own after his mother was killed and he became too weak to continue the journey due to shrapnel wounds.

Another family reported the death of a baby who died in the heat after being separated from her mother as they fled across the border. Save the Children also received reports of children being targeted by sniper fire, forced to take flight under heavy shelling and driven to licking moisture from leaves in a desperate attempt to stave off thirst in the searing heat.

The reports, gathered by Save the Children ahead of World Refugee Day, paint a disturbing picture of the desperation and horror faced by Syrian children as they seek to escape the violence in the country. Some of the most graphic reports include:

A 12 year-old boy — whose mother had been shot — being left to bleed to death with insect-eaten shrapnel wounds as the group he was with were forced to abandon him and run for their lives

A baby separated from her mother dying in the heat due to a lack of milk

Children being trampled underfoot as desperate civilians run for their lives under shell fire

A 13 year-old girl being shot through her thigh during an escape attempt

A 16-year-old beaten with sticks and displaying signs of physical torture after 15 days' detention and interrogation

A 12-year-old boy having his throat cut by personnel manning a checkpoint

There are currently 1.6 million people from Syria in need of refugee assistance in Jordan, Turkey, Lebanon, Iraq and Egypt. The number of registered refugees has increased 17-fold in the past 12 months and the number is expected to reach 2 million this summer.

The number of people in need of refugee assistance from Syria has increased on average by close to a third each month for the past year. Were that trend to continue, Syria would be emptied of civilians by as early as April 2014.

"The horrific stories we've gathered from refugees over the past few days show how children are bearing the brunt of the Syrian conflict. Children in Syria are being killed, tortured, recruited as soldiers and abused in horrifying numbers. Children are being separated from their parents, and some are dying alone at the roadside from their wounds," said Carolyn Miles, president and CEO of Save the Children.

"Meanwhile conditions are proving too much for the weakest and most vulnerable babies. Millions of children are beyond the reach of humanitarian aid and have no option but to flee. Over half of all Syrian refugees are children and behind the terrifying statistics of civilians fleeing their country are millions of individual tragedies.

"Ultimately the only solution to this crisis is an end to the violence in Syria, but in the meantime, we urgently need to be able to reach those trapped inside Syria. Unless we can, I am afraid we will hear more horrifying stories of children forced into ever more desperate circumstances."

Children inside Syria are especially vulnerable to the worst atrocities of the crisis. Those who manage to escape often lack access to schools and safe places to play and are frequently living in cramped, overcrowded conditions.

As well as working with refugee communities in Lebanon, Jordan and Iraq, Save the Children is working across Syria to bring vital humanitarian aid to the most vulnerable communities. However, due to restrictions posed by a lack of access, it is currently only reaching 10 percent of those people they aim to reach inside the country itself.

Save the Childrenis the leading independent organization for children in need, with programs in 120 countries, including the United States. We aim to inspire breakthroughs in the way the world treats children, and to achieve immediate and lasting change in their lives by improving their health, education and economic opportunities. In times of acute crisis, we mobilize rapid assistance to help children recover from the effects of war, conflict and natural disasters. Follow us onTwitterandFacebook.

Save the Children invests in childhood – every day, in times of crisis and for our future. In the United States and around the world, we give children a healthy start, the opportunity to learn and protection from harm.

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